About 212 light-years from Earth, giant gas light is enough to be described as a “super-puff” or “cotton candy” planet orbiting very close to its host star. The exoplanet so light, astronomers are left questioning everything we knew before about how gas giants perform.
This super-puff exoplanet, known as WASP-107b, is about the size of Jupiter, but only about one-tenth the mass – or about 30 times larger than Earth. According to a new study published Monday in the Astronomical Journal, its main mass is much smaller than astronomers thought necessary to create a massive gas planet like Jupiter and Saturn.
The discovery, made by a Ph.D. student Caroline Piaulet, led by Professor Björn Benneke at the University of Montreal, reveals that creating gas giants is much easier than previously believed.
“This study pushes the limits of our theoretical understanding of how large size planets form. WASP-107b is one of the most puffiest planets out there, and we need a creative solution to explain how for these tiny corries to build such huge gas envelopes, “coauthor Eve Lee said in a statement.
WASP-107b is not a fancy new discovery – astronomers first discovered it in the constellation Virgo in 2017. The planet is very close to its star, more than 16 times closer than Earth to the sun, completing one orbit every 5.7 days.
WASP-107b is one of the most dense exoplanets scientists have ever discovered. They have nicknamed planet-like types – gas giants with cotton candy density – super-puffs.
ESA / HUBBLE, NASA, M. KORNMESSER
To discover the planet’s incredible mass, astronomers studied observations made at the Keck Observatory in Hawaii. They used a method called the radial velocity method, which studies the moving motion of a planetary star caused by the gravity of a planet, to work out the mass.
Scientists were surprised to conclude that the solid core of WASP-107b has a mass no larger than four times that of Earth, which means that more than 85% of its mass is coming from the thick gaseous layer around the heart. This is a very different breakdown from Neptune, which has an equal mass but keeps only 5% to 15% of it within its gas level.
Based on their knowledge of Jupiter and Saturn, scientists previously believed that a solid core would need at least 10 times the mass of the Earth to get enough gas to create a giant gas planet. WASP-107b challenges that theory.
“This work addresses the real foundations of how large planets can grow and flourish,” said Benneke. “It provides concrete proof that a large accumulation of gas cans can be stimulated for not as big as expected. “
Lee says, “The most plausible scenario is that the planet created far away from the star, where the gas in the disk is cold enough that gas accumulation can happen very quickly. It was possible to the planet migrating into its normal position, either through interaction with the disk or with other planets in the system. “
While exploring the planet, the team went down on another one in the same system, WASP-107c. It has a mass of about one-third that of Jupiter and will take three years to orbit its host star once.
The oval-shaped orbit of the planet suggests that the new idea of astronauts is on the right track.
“WASP-107c has, in some ways, memorized what happened in its system,” Piaulet said. “Its great wonder is advertising at a time of great chaos, with interactions between the planets that could have caused major movements, such as the suspect for WASP-107b. “
The team hopes to continue exploring the strange planet with the launch of the James Webb space telescope this year.